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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

From Alphas to Epsilons : A study of eugenics and social caste in Aldous Huxley’s Brave New World from a biographicalperspective

Kringstad, Johan January 2017 (has links)
AbstractThis essay discusses the concepts of eugenics and social caste in Brave New Worldin relation to Aldous Huxley, from a biographical perspective. The essay analyzes how events and personal relationships of Aldous Huxley have influenced the depiction of the concepts social caste and eugenics in his novel Brave New World. Using sources which recount the travels and the personal encounters that Aldous Huxley made throughout his life, this essay makes comparisons and draws conclusions as to how these eventsand relationshipshave affected the depiction of social caste and eugenics in Brave New World
82

Managing teachers in low-income countries

Karachiwalla, Naureen Iqbal January 2013 (has links)
Apart from the introduction (Chapter 1) and conclusion (Chapter 7), this thesis comprises five chapters organized into two parts: Part I studies promotion incentives in the public sector, and focuses on the case of teachers in rural China. All teachers in China compete with their colleagues for rank promotions. I aim to answer two questions: first, whether the promotion system for teachers in China elicits effort from teachers, and second, how the design features of the promotion system affect effort incentives. Part I includes four chapters. Chapter 2 introduces the topic and provides a background on promotions for teachers in China. It also discusses related work in this area, and introduces the data that will be used in Part I. Chapter 3 presents and tests a theoretical model of promotions as an incentive device. The model treats all teachers as identical in terms of their ability, and as such, focuses on average levels of teacher effort. It predicts that effort is exerted in response to potential promotions. In addition, the model also predicts that average effort incentives are higher in promotion contests in which the wage gap is higher, the promotion rate is closer to one half, the number of teachers competing for a promotion is higher (for promotion rates between 1/3 and 2/3), and the average age of teachers in the contest is lower, or the proportion of female teachers is lower. The model is used to derive an estimating equation by which to test predictions on average levels of teacher effort. An equation is estimated for the probability of promotion as a function of teacher effort, which is proxied by the teachers' annual performance evaluation scores. There is simultaneity present as effort increases the probability of promotion, but it is also the promise of promotion that motivates effort. As a result, effort is instrumented using wage changes, which are both informative (higher wage gaps are associated with higher effort) and valid (wages only affect promotions through effort). The second stage of the regression demonstrates that effort is indeed exerted by teachers in order to win promotions. The first stage confirms the predictions of the model with regards to wage gaps, the promotion rate, and the size and composition of the pool of competitors. Chapter 4 extends the model of Chapter 3 in two ways: teachers are now treated as heterogeneous in ability, and a multi-period model of teacher effort over time is also added. This chapter focuses on individual levels of teacher effort, and on how the parameters of the promotion system interact with teacher characteristics to affect teacher effort. The predictions include that teachers in the extremes of the skill distribution will have lower incentives, and as the contest size increases these teachers will have effort incentives that are lower still, that teachers who are five or more years from promotion eligibility will have zero effort, as will teachers in the highest rank, that teacher effort will increase in the five years leading up to promotion eligibility, and that teacher effort will decrease after a teacher is eligible for promotion but has been passed over several times. An effort equation is estimated that captures all of these components, and the predictions are largely affirmed by the data. Tests are conducted in order to alleviate concerns about selection, as well as measurement error in the performance evaluation scores. Chapter 5 concludes Part I. Part II of this thesis looks at teacher labour markets, social distance, and learning outcomes in Punjab, Pakistan. Chapter 6 explores the link between the distribution of teachers in the labour market, caste differences between teachers and students, and child learning outcomes. Using rich longitudinal data from Pakistan that allows me to convincingly identify the causal effects of caste on learning outcomes, I show how the distribution of teachers across public schools induces particular matches of high and low caste teachers and students, and that these matches are highly predictive of test score outcomes. Specifically, low caste male children perform significantly better when taught by high caste teachers than when they are taught by low caste teachers. Several possible channels are explored, including discrimination in the classroom, role model effects, teacher quality, patronage, peer effects, and returns to education. Although the channel cannot be proven, the data points to high caste teachers being able to raise the already high returns to education for low caste children because they are able to assist these children in getting educational benefits and employment later on using their patronage networks. Low caste children therefore work harder to impress high caste teachers, and this results in higher learning outcomes.
83

Within the limits : respectability, class and gender in Hyderabad

Gilbertson, Amanda Kate January 2011 (has links)
Drawing on twelve months of fieldwork in suburban Hyderabad, India, this thesis contributes to emerging debates on the Indian new middle classes and postcolonial middle classes more generally. I challenge images of a homogenous middle class enjoying the benefits of liberalization by highlighting the diversity in wealth, lifestyle and access to opportunities within this class sector. Contrary to the pervasive image of a hedonistic and morally corrupt new middle class, I assert the centrality of moral discourses to the construction of middle-class identity in Hyderabad. Middle-class Hyderabadis engage in moral discourses of ‘respectability’ and ‘open-mindedness’ in relation to caste, consumption, education, and women’s public and domestic roles. These discourses of morality are central to the reproduction of class and gender inequality as successfully balancing the demands of respectability and open-mindedness is particularly difficult for those with fewer resources such as the lower middle class and for women who are expected to embody authentic Indianness in their demure comportment, ‘traditional’ attire and commitment to ‘Indian’ family values, but are also liable to being judged ‘backward’ if their clothing and lack of education and paid employment are seen to be in conflict with fashion and open-mindedness. The focus on balance and compromise in middle-class Hyderabadis’ narratives echoes other work on postcolonial middle classes that has emphasised people’s efforts to adhere to local notions of respectable behaviour that are central to national identities while also attempting to align themselves with a ‘modern’ global consumer culture. In contrast to much of this literature, however, I challenge the notion that modernity and tradition, the local and the global are objects of desire in and of themselves and instead argue that they function as important reference points in discourses that legitimate the dominant position of men and those of upper class-caste status.
84

The educational and occupational aspirations of young Sikh adults : an ethnographic study of the discourses and narratives of parents, teachers and adults in one London school

Brar, Bikram Singh January 2011 (has links)
This research study explores how future educational and occupational aspirations are constructed by young Sikh adults. Semi-structured interviews were conducted with ten young Sikh adults, both their parents, and their teachers at one school in West London to investigate how future aspirations are constructed, which resources are employed, and why certain resources are used over others. In some previous research on aspirations and future choices, Sikhs have either been ignored or, instead, subsumed under the umbrella category of 'Asian' and this study seeks to address this. Furthermore, the study seeks to shed light on how British-Sikh identities are constructed and intersected by social class, caste and gender. This is important to explore since it can have an impact upon how young adults are structured by educational policy. A 'syncretic' social constructionist framework which predominantly draws upon Pierre Bourdieu's notions of habitus, capital and field, along with the cultural identity theories of Avtar Brah and Stuart Hall, is employed to investigate the construction of identities and aspirations. In addition, the study contains ethnographical elements as it is conducted on my 'own' Sikh group and at my former secondary school. Consequently, I brought a set of assumptions to the research which, rather than disregard, I acknowledge since they highlight how I come to form certain interpretations of phenomena over others.
85

Recrutamento e marcação química de trilha em Atta sexdens rubropilosa (Hymenoptera: Formicidae) sob diferentes fontes de estímulos / Recruitment and chemical-marked trail in Atta sexdens rubropilosa (Hymenoptera: Formicidae) to different stimuli

Sujimoto, Fernando Ribeiro 30 January 2014 (has links)
A formação, recrutamento e manutenção de trilhas em formigas cortadeiras do gênero Atta é controlada quimicamente e envolve a participação de diferentes castas. Todavia, são escassos os estudos sobre a dinâmica das castas sob diferentes fontes de estímulos para a colônia, e como isso interfere na deposição de trilhas químicas. O presente trabalho visou compreender a influência de diferentes fontes de estímulos no padrão químico de deposição das trilhas, bem como no comportamento de recrutamento, forrageamento e defesa das operárias em Atta sexdens rubropilosa (Hymenoptera: Formicidae). Os resultados indicaram que houve variação do perfil etológico e alocação de tarefas desempenhadas pelos indivíduos presentes na colônia, de acordo com a fonte de estímulo. Neste caso foram oferecidos uma fonte de estímulo atrativa (\"pétalas de rosas\") e outra de agressividade (\"rainha de outra colônia\"). Além disso, os perfis químicos observados nas trilhas variaram qualitativamente e quantitativamente de acordo com os estímulos oferecidos. Estes dados sugerem que as operárias de A. sexdens rubropilosa seriam capazes de manejar quimicamente seu feromônio de trilha para informar e alterar o comportamento de suas companheiras de ninho, de acordo com a fonte de estímulo em que foram expostas. / Formation, recruitment and maintenance of trail in Atta leaf-cutting ants are chemically controlled and involve participation of different castes. Nevertheless, studies on caste dynamic under different stimuli to the colony are scarce, and how it interferes in the chemical deposition of the trail. This investigation aimed to understand how different source of stimuli influence the chemical pattern of trail marking as well as the recruitment, foraging and defense behavior by workers in Atta sexdens rubropilosa (Hymenoptera: Formicidae). Results indicate variation in the ethological profile and task allocation performed by the colony individuals, according to the stimuli source. In this case, it was offered an attractive stimulus source (\"rose petals\") and an aggressive one (\"other colony queen\"). Moreover, the chemical profiles of the trail varied qualitatively and quantitatively in response to the stimuli they were exposed. These data suggest that A. sexdens rubropilosa workers would be able to chemically manipulate their trail pheromone with aim to inform and alter their nestmate behavior in response to the exposed stimuli source.
86

Foundations of Anti-caste Consciousness: Pandit Iyothee Thass, Tamil Buddhism, and the Marginalized in South India

Ayyathurai, Gajendran January 2011 (has links)
This dissertation is about an anti-caste movement among Dalits (the oppressed as untouchable) in South India, the Parayar. Since the late 19th century, members of this caste, and a few others from Tamil-speaking areas, have been choosing to convert to Buddhism based on conscience and conviction. This phenomenon of religious conversion-social transformation is this study's focus. By combining archival research of Parayar's writings among Tamil Buddhists, as these Parayar, settled in Tamil Nadu and Karnataka, are called, I have attempted to understand this movement ethno-historically. In pre-colonial times, though the sub-continent's societies were hierarchical, the hierarchies were fluid and varied: i.e., the high-low or self-other dichotomies were neither fixed nor based on a single principle. The most significant effect of the encounter of British Colonialism and India was to precipitate an unprecedented master-dichotomy of singular and absolute form of self and other, as colonizer and the colonized. This had three consequences. (a) India was itself seen as singular and served as the Self to the colonial Other in an absolute dichotomy; (b) the role of essentializing the Indian Self was assumed by the brahmin; (c) this in turn resulted in an internal dichotomy between the brahmin-essential self and the non-brahmin-non-essential other. The means chosen to fix this dichotomy was to nominate the non-essential other's paradigmatic representation, the Dalit. I intend to read against the grain of the binary logic that was inaugurated at the moment of the colonial encounter by means of Tamil Buddhists' oppositional, reconstructional, and representationaldiscursive practices.
87

Ordering Subjects: Merchants, the State, and Krishna Devotion in Eighteenth-Century Marwar

Cherian, Divya January 2015 (has links)
“Ordering Subjects” argues that the merchants of Marwar led efforts to demarcate a new, exclusive community of elites, one that they conceptualized of as self-consciously ‘Hindu’ and forged through the application of state power. This early modern Hindu community defined itself in opposition not to the figure of the Muslim but to that of the ‘Untouchable,’ a category that included but was not limited to the Muslim. The early modern Hindu identity was thus deeply imagined in caste terms. This elite community organized around Krishna devotion, especially the Vallabh Sampraday, and demarcated itself through cultural markers such as the practice of vegetarianism, teetotalism, and austerity. Merchants, often joined by brāhmaṇs, waged their battles for the demarcation of this new community by petitioning the crown and by successfully deploying the control that they had gained in prior centuries over the state apparatus as bureaucrats. State power, consisting of its judicial, fiscal, recordkeeping, and surveillance mechanisms, played a central role in the implementation of laws and regulations, including spatial, economic, social, and ritual segregation, enforced vegetarianism, and the moral policing of elite subjects’ lives. Most of these petitions and state responses were legitimized with reference to ethics, marking a departure from the until-then prevalent emphasis on custom as the basis for legislating society. “Ordering Subjects” suggests that this marked a shift towards a more universal law and that the turn to ethical principles made possible the disregard for the force of custom that these departures marked. Further, the dissertation demonstrates that these processes enabled the ascendance of a mercantile ethos as the preeminent cultural code of the region, displacing that of the warrior and modifying that of the brāhmaṇ. Lastly, it shows the extent to which the state in eighteenth century Marwar had penetrated society and was capable of intervening in it using surveillance and judicial methods. The dissertation challenges the current scholarly framing of the debate over the existence of religious identities in pre-colonial South Asia, suggesting that it casts modern, binary (‘Hindu-Muslim’) conceptions of religion, as distinct from politics, upon pre-modern history. Instead, “Ordering Subjects” points to the role of caste, as a field of politics, in determining the contours and imagination of early modern Hindu identity. It offers a political and social history of Krishna devotion, extending scholarship on this field beyond the focus on its literary, theological, and cultural aspects that currently dominate the field. In tracing the local effects of the global processes of economic circulation and integration that characterized early modernity upon social and political life of a landlocked kingdom, the dissertation offers a perspective upon the history of early modern South Asia as it unfolded away from, but in connection with, the ports and court cities of the region.
88

The Fights of the Forsaken Kings: Caste Conglomeration, Heroism, and Sovereignty in Contemporary South India

Gross, Victoria Gabrielle January 2017 (has links)
This ethnographic and archival study offers insight into Dalit identity politics, Tamil ethno-nationalism, and affective understandings and experiences of sovereignty in contemporary Tamil Nadu, South India. It is an-depth exploration of the recent history and present moment of inter-caste conflict that plagues Tamil Nadu, despite the fact that it is India’s most urbanized state, and among its wealthiest and most industrially developed. Over the course of the past thirty years, spectacular and brutal murders, riots, and police repression have regularly characterized the relationships between groups of politically affiliated individuals we call castes. I historicize and contextualize such incidents, tracking the changing phenomenology of caste as it intersects with the gendered politics of Tamil ethnic identity. In order to do so, I examine the formation of caste conglomerations, which I define as intentionally incorporated political bodies attempting to situate themselves relationally in the context of rapid demographic and technological changes, and the breakdown of formal, intergenerational models of caste differentiation and hierarchy. The practices of intercaste relations in Tamil Nadu, are not disappearing, but are asserting themselves in new and sometimes violent ways as the economic realities and inhabitable spaces of many formerly distinguishable castes become increasingly alike. Responding to the anxiety of disintegrating hierarchy, what were once localized, relatively independent castes are uniting as political bodies that attempt to identify themselves in relation to each other, competing mimetically in a cycle of recursive opposition. I focus on two increasingly visible caste conglomerations – the Devendras and the Thevars – who have been embroiled in a violent conflict in Tamil Nadu since the late 1950s. The recent experiences of the Devendras who are officially classified as Dalit (“untouchable”), and the Thevars who were once socioeconomically dominant in much of Southern Tamil Nadu, exemplify the changing socioeconomic dynamics that foster caste conglomeration. Although the ancestors of many landowning castes ruled over the laborers they relegated to untouchability, their recent economic decline relative to the “untouchables” has unsettled what were once clearly demarcated social hierarchies. A new and unstable economy of collective rank is developing to fill this vacuum, as the self-fashioned leaders of caste conglomerations construct their identities. The process of caste conglomeration dissolves antecedent boundaries of caste even as it reconstitutes castes as larger and therefore more powerful groups, thus simultaneously demonstrating both the fluidity and intractability of caste logics.  The identitarian claims of caste conglomerations are carved into the new urban spaces they inhabit with visual and auditory signifiers, which are heightened during memorial celebrations of recently remembered caste history. Caste heroes who embody the often conflicting Tamil masculine ideals of selfless courage and refined civility play an important role in such acts of representing history through which caste conglomerations proclaim the dignity they are owed in the present through the glories of their past. I explore this process as it is energized by the antagonistic power struggle between the Devendras and the Thevars. The still tenuously united Devendras fight back against their relegation to Dalit status by claiming that they have been misclassified in the caste order, and that they are not, in fact, Dalits. Instead, they are the original people, and therefore rightful rulers, of the Tamil country. The Thevars who are a slightly older conglomeration of three previously endogamous but similarly ranked castes, counter such claims with their own claims to Tamil sovereignty, contributing to the unintended fallout of Tamil ethno-nationalism, or Dravidianism. Dominating state-level politics since the middle of the twentieth century, Dravidianism has attempted to configure a united non-Brahmin identity, which might have dissolved the boundaries between the vast majority of Tamil castes. It has instead resulted in widespread, caste-based competition over Tamil identity. The Devendras are increasingly vying for power through the idiom of Tamil identity, distancing themselves from Dalits (themselves an enormous caste conglomeration founded on the disavowal of caste), despite the Dalits’ electoral success. In tracing the Devendras’ strategy, my dissertation locates the boundary of pan-Indic Dalit political identity, suggesting that the Dalit category inadequately describes the experiences of formerly “untouchable” groups who are drawn, like many others, to the powerful calls of ethnicity. Such struggles of caste, entangled with ethno-nationalism, demonstrate the yearning for sovereignty that has arisen alongside the distrusted state. The parties and caste organizations of the Devendras and Thevars, like those of other rapidly multiplying caste conglomerations, reflect the desires of the disempowered, and operate as parastate authorities offering material benefits, collective pride, and transactions with government agents, which are troubled by the conglomerations’ need for legitimation that only the government can offer. These complicated processes of negotiating new and relatively unstable economies of power drive the questions of my dissertation, which unfold through the stories of Tamil men who experience the forces of caste identity and the government in their everyday lives. Caste conglomeration is not another example of Sanskritization through which castes ascend the social ladder by emulating those above them. Instead, the process I examine is competitive, mimetic, and recursive, presupposing the relative equality brought about by economic changes and by the promises of the democratic nation-state. While one generation ago, there were stark differences between landowning castes and the laboring castes now known as Devendras, today, Devendras have the resources to compete in terms of their public visibility, levels of education, and historical claims. In fact, their assertions are so resounding that Thevars sometimes follow Devendras in their strategic calls for recognition. I do not, however, discount the brutalities of Thevar violence against Devendras, but instead aim to shed light on the social context of such acts. It is the profound anxiety of growing similarity, rather than difference, that erupts in the excess of violence.
89

Revisão taxonômica e análise filogenética do gênero Hylomyrma Forel, 1912 (Formicidae: Myrmicinae: Pogonomyrmecini), com base em dados morfológicos / Taxonomic review and phylogenetic analysis of the genus Hylomyrma Forel, 1912 (Formicidae: Myrmicinae: Pogonomyrmecini), based on morphological data.

Ulysséa, Mônica Antunes 14 July 2017 (has links)
A subfamília Myrmicinae é um grande desafio à sistemática de formigas por ser a maior e mais diversa subfamília de Formicidae, abrangendo cerca de seis mil espécies distribuídas mundialmente. As relações filogenéticas internas desta subfamília são fonte de discussão e incerteza na literatura. Os estudos moleculares desenvolvidos em Attini e Myrmicini (sensu Bolton) representaram os primeiros passos para a compreensão dos clados existentes em Myrmicinae. Recentemente, as 25 tribos estabelecidas para esta subfamília foram reorganizadas em apenas seis Attini, Crematogastrini, Myrmicini, Pogonomyrmecini, Solenopsidini e Stenammini. Hylomyrma Forel, 1912 o grupo objeto deste estudo atualmente pertence à tribo Pogonomyrmecini junto com outros dois gêneros, Patagonomyrmex Johnson & Moreau, 2016 e Pogonomyrmex Mayr, 1868. Hylomyrma é um gênero exclusivamente Neotropical cujas espécies habitam a serapilheira. Em decorrência do hábito críptico das espécies, a diversidade e a história natural do grupo são pouco conhecidas. Desde a revisão realizada por Kempf (1973), que reconheceu 12 espécies para o gênero, poucas foram as espécies incluídas em estudos filogenéticos e apenas uma espécie foi descrita posteriormente. O presente estudo teve por objetivo realizar um estudo de revisão taxonômica a partir da análise de uma quantidade extensa de material e investigar pela primeira vez as relações filogenéticas internas do gênero com base em caracteres morfológicos externos de operárias. Praticamente todos os espécimes-tipo designados para as espécies de Hylomyrma (com exceção do holótipo de H. reginae Kutter, 1977) foram examinados, além de 2.757 exemplares provenientes de 29 instituições. Quinze espécies novas foram reconhecidas, sendo 10 descritas com base tanto em operárias quanto em gines. Novos dados de distribuição foram registrados para as 13 espécies já conhecidas, bem como a descrição de cinco gines e seis machos. Além disso, o estudo taxonômico indica que a presença de espécimes cuja morfologia externa representa um mosaico entre gine e operária (intercastas) não é incomum no grupo, sendo observada para 11 espécies. O estudo filogenético foi realizado a partir de uma matriz composta por 88 caracteres e 31 terminais, sendo três espécies do grupo-externo. As análises de máxima parcimônia (MP) foram realizadas no programa TNT através de buscas tradicionais empregando o algorítmo de rearranjo de ramos TBR com 3.000 réplicas, 10 árvores salvas por réplica, random seed=0 e colapse trees=ON, sob esquemas de pesagem igual e implícitos. Os valores de concavidade (k) utilizados variaram entre 1-25. O suporte dos ramos foi calculado através do índice de Bremer. A análise com pesagem igual resultou em uma árvore com 269.274 passos (IC=0,379 e RI=0,59). Quatro diferentes árvores foram obtidas a partir das análises com pesagem implícita, k1, k3-9, k15 e k20-25. O resultado da análise filogenética corrobora a monofilia de Hylomyrma, com pelo menos nove sinapomorfias sustentando esta hipótese de agrupamento. Três grandes linhagens podem ser reconhecidas em Hylomyrma: A, espécies com tamanho corporal relativamente grande (car. 52, variando de 0,534 a 0,785); B, espécies com face posterior do pró-fêmur lisa (car. 45 1), estriação do primeiro tergito gastral restrita à base do segmento (car. 79 0) e presença de pelos ramificados no primeiro tergito do gáster (car. 85 1), condição posteriormente perdida por Hylomyrma sp. T; e C, caracterizado por espécies cujos pelos apresentam ramificações de tamanho igual (car. 15 0) e superfície dorsal do mesonoto com estriação irregular (car. 19 4). O conhecimento sobre a biologia das espécies de Hylomyrma é ainda bastante incipiente e grande parte das informações é proveniente de dados de rótulo e de raras observações em campo. As espécies deste grupo são comumente coletadas em amostras de serapilheira em florestas úmidas e secas, e plantações em locais ao nível do mar até elevações de 3.600 m. Aparentemente, as colônias de Hylomyrma são bastante pequenas, os ninhos são feitos em pequenos galhos caídos na serapilheira, os indivíduos são capazes de se fingir de mortos (tanatose) (observações pessoais) e as espécies apresentam dieta generalista. Como etapas futuras para a melhor compreensão deste grupo, sugere-se uma análise das relações internas dos gêneros através de ferramentas moleculares e a utilização de caracteres morfológicos de gines, bem como o estudo dos padrões biogeográficos e o estudo mais detalhado das intercastas para o entendimento da evolução de novidades morfológicas. / The subfamily Myrmicinae is a major challenge to ant systematics due to its outstanding diversity, which encompasses nearly six thousand species distributed worldwide. Phylogenetic relationships within this speciose subfamily are still subject to controversy in the literature. Molecular-based studies in Attini and Myrmicini (sensu Bolton) were the first to provide phylogenetic hypotheses for relationships within Myrmicinae. More recently, the twenty-five tribes of Myrmicinae were reorganized into only six Attini, Crematogastrini, Myrmicini, Pogonomyrmecini, Solenopsidini, and Stenammini. Hylomyrma Forel, 1912 the focal group of this study is currently classified in the tribe Pogonomyrmecini, along with two other genera, Patagonomyrmex Johnson & Moreau, 2016 and Pogonomyrmex Mayr, 1868. Members of Hylomyrma are exclusively found in the Neotropics, and live in leaf-litter. Due to their cryptic habits, the diversity and natural history of Hylomyrma species are still poorly known. Since the revision of Kempf (1973), who recognized 12 species in the genus, few representatives of Hylomyrma have been included in phylogenetic studies, and one species was described. Presented here is the first phylogenetic analysis of Hylomyrma based on a comprehensive taxon sampling, which is used as basis for a taxonomic revision of the genus. This study includes data retrieved from first-hand examination of nearly all types (except for the holotype of H. reginae Kutter, 1977), in addition to 2.757 exemplars from 29 institutions. Fifteen new species of Hylomyrma are recognized, ten of which were characterized based on worker and gyne morphology. New distribution records are provided for the thirteen previously known species, as well as morphological descriptions for gynes and males (in five and six species, respectively). Specimens showing features from both gynes and workers were observed in 11 species, suggesting that intercastes are not uncommon in this group. Phylogenetic analyses were performed on a matrix comprising 88 characters and 31 terminal taxa, including three species as outgroups. Maximum parsimony (MP) reconstructions were computed on the software TNT. The traditional search analysis were implemented with 3,000 replicates using the TBR algorithm, 10 trees saved per replication, random seed=0 and colapse trees=ON, under equal and implied weighing schemes. The concavity values (k) used were set between 1-25. The branch support was calculated by Bremer score. Unweighted MP analyses resulted in one cladogram with 269.274 steps (IC=0.379 and RI=0.59). Four different topologies were obtained for the following k intervals k1, k3-9, k15 and k20-25. Results strongly corroborate Hylomyrma as a monophyletic clade defined by nine synapomorphies. Internal phylogenetic relationships indicate three main lineages: A, species with large body lenght (char. 52, ranging from 0.534 to 0.785); B, species with posterior face of the anterior leg shiny (char. 45 1), first gastral tergite with very short striae (char. 79 0) and multibranched hairs (char. 85 1), condition subsequently lost by Hylomyrma sp. T; and C, characterized by species with multibranched hairs, being the branch with the same size (car. 15 0) and irregular striae on mesonotum dorsal side (car. 19 4). Natural history data, still unavailable for most Hylomyrma species, is mostly obtained from labels and scattered field observations. Exemplars are usually collected in leaf-litter samples in wet and dry forests, and cultivated areas from sea level up to elevations at 3,600 m. Hylomyrma colonies are apparently small, nests are made from small branches found in the leaf-litter, and these generalist ants which take on the appearance of being dead when they are threatened (thanatosis) (personal observations). Future developments in the systematics of Hylomyrma should include morphological characters based on gynes and molecular characters to increase the resolution of internal relationships, which will also allow the investigation of biogeographic patterns. A more detailed study of intercastes will shed light on the evolution of morphological novelties in ants.
90

Educational policies serving the poor : A case study of student's performance in Indian hostels

Lindén, Rut January 2005 (has links)
<p>This study examines the effect on school achievement of a policy such as hostels, aimed at</p><p>giving children from a poor socioeconomic background an opportunity to receive education.</p><p>Data is collected from two different schools in a district in Andhra Pradesh, India, in which</p><p>both hostel students and day-scholar students, having a similar background, are studying.</p><p>Exam scores for three different subjects are used as dependent variables in the analysis. The</p><p>results indicate that private hostels do have a positive effect on achievement in all subjects,</p><p>thereby contributing to reducing the large gap in school achievement between different</p><p>socioeconomic groups</p>

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